Little is known about the genetics of the bdellovibrios, and a system for introducing DNA into bdellovibrios has only recently been reported. The development of a map of the bdellovibrio chromosome would serve as a stimulus for additional genetic studies and a framework onto which genetic data could be coordinated. The overall objectives are to construct a physical map of the Bdellovibrio bacteriovorus genome, to compare the physical maps of several bdellovibrio strains, and to locate a number of genes on the map. High quality, unsheared genomic DNA will be extracted from Bdellovibrio bacteriovorus 109J, and several other strains, into agarose beads. The DNA will be cut with rare cutting restriction endonucleases, and the resulting large DNA fragments separated using pulsed field gel electrophoresis. The restriction patterns, or fingerprints, of various strains will be compared in order to determine relatedness and taxonomic significance. Restriction fragments will be ordered relative to each other. This will be accomplished by 1)using fragments of one enzyme digest to probe Southern blots of different enzyme restriction patterns to discover overlaps between fragments; 2)probing Bdellovibrio genomic YAC clones with isolated genomic restriction fragments. The beginnings of a genetic map will be originated by positioning cloned genes and transposon insertions on the physical map.